1. Field of the Invention
The present invention is related to a monitoring apparatus for monitoring the operating condition of transmission facilities of communications transmission technology which are composed of assemblies in which the monitoring apparatus requires both trouble reports and measured values and contains a monitoring information generator which is connectible, together with monitoring information generators of further monitoring apparatus, to signal collectors of a signal collecting device for central operation observation.
2. Description of the Prior Art
E. Diggelmann, B. Luescher, "Die Alarmregistrieranlage AREGA A 150", Hasler-Mitteilungen, No. 3, 1975, pp. 77-88, discloses the use of a process control computer for the periodic interrogation of a great number of inputs in order to obtain the most accurate information possible regarding the disturbance behavior of a transmission network. This known system contains a sampling system. The sampling system is composed of a sample control unit and up to four sample multiplexers. The multiplexers allow a group-by-group interrogation of the signal stage by the sample control unit which, among other things, has the task of comparing the signal states to the states of the preceding sample cycle and of writing all deviations in a special form into a line number memory where they are further processed.
Two signals are brought to the alarm registration system for every line to be monitored. These two signals can exhibit only two states. The signal states whether a line is disturbed or undisturbed; the other signal states whether an alarm bell is switched on or off.
In the evaluation, the disturbances are divided into three classes depending upon duration. Sequence reports are also suppressed.
Comparatively frequent alarms, given faults or disturbances identified in communications transmission, can be the reason that a communications transmission link is subjected to special observation. For example, given comparatively frequent fault alarms in digital systems, a code error test position or, respectively, a test position for the acquisition of the wrong frame recognition words, can be installed at a suitable location and the test results can be evaluated on the basis of a tape printer protocol. In particular, one can check whether the respective requirements made of the transmission quality, as can be prescribed by the requirement G821 of the CCITT, or the like, are fulfilled. Even given an evaluation by a computer involved in the test position, this involves considerable expense, particularly when many transmission systems are to be simultaneously monitored.